Well best case scenario is to kill the artillery (many use shadowstrike starhost for this type of thing) or at least tie it in combat so it can't shoot whatever it wants. However, I understand that this is often not possible. The dread saurian has a good save and it heals, AND it has 16 wounds, so even if it takes 10 mortal wounds it may be okay. That 10 mortal wounds would go onto SOMETHING! If he's shooting at your dread saurian, he's not shooting at something else, so use that other thing to mess him up

Yeah, Chameleon Skinks value isn't as assassins (although they can be). Their real value is their ability to tie big threats up for a turn. Being able to set up Anywhere on the battlefield allows you to ignore the normal distance and placement rules. You can throw them directly into combat. Forcing enemies to spend a turn shooting & or fighting them in combat.

To have the highest chances to have your DS in melee in the first turn, you should cast Curse of fate on the Beast, before teleport it with LoSaT (successful teleport on 2-3, teleport and move on 4-6)

If you roll a 2-3, the charge will happen on a roll of 8, that you can reroll with a command point, if you have a hero nearby (not so hard, given the size of the DS)
Bonus point if you have the Hunter constellation (+1 to charge)

Also if you're Curse of Fate-ing it you can then also use the +1 to a dice in the combat phase to increase a wound roll from a 5 to a 6 and trigger the starpriest's Serpent Staff if you've popped it on Dready, a casual 12 damage